Hi Dalia

One source will give you a sound reading, but this will be local to where the reading is taken. Many readings will pick up all the minutely local variances which will overall iron out the variances in acoustics at each precise location. Thus, with many readings, you would be able to get an overall average of what the ambient sound would be.

If, for example, there was a specific sound source, each smartphone might be oriented in a different way, which would mean they would all record potentially different sound volumes. You could then do some statistical analysis to work out what the average sound level would be.

With some smart analysis, you could glean a lot of useful information with many sources, whereas with one, the value is likely to be less.

I hope that helps.

Regards

Bob

In crowd sourcing you will require good volunteers to get optimal results. Knowing that there is no free lunch, you may opt for some reward system for crowd sourcing volunteers. And obviosuly, you will require a good quantity of different such volunteers.

Thank you so much